MirrorDisk/UX

[Learn_1]

Hi All,
we have rp7410 server running HP-UX11i.i want to mirror local system disk with the second one of the local system.i have Mirror/UX software installed.Now what would be the procedure of mirroring these local disk with each other.Also in case of failure of any disk what would be the recovery procedure.Please be specific to commands and script.Also as this is a live system then after completion of mirroring procedure does it reboot system or we'll have to rebot system.
Thanks.

[Kenneth_19 · Accepted solution]

Hi,

1. Create the physical volume on the disk that you are going to mirror your root disk to:

# pvcreate -Bf /dev/rdsk/c?t?d?

2. Make disk bootable

# mkboot /dev/dsk/c?t?d?

3. Add auto file to boot area

# mkboot -a "hpux (;0)/stand/vmunix" /dev/dsk/c?t?d?

4. Extend the root vg with the new boot disk

# vgextend vg00 /dev/dsk/c?t?d?

5. Extend the LV in the root disks one by one:

# lvextend -m 1 /dev/vg00/lvol1 /dev/dsk/c?t?d?
# lvextend -m 1 /dev/vg00/lvol3 /dev/dsk/c?t?d?
# lvextend -m 1 /dev/vg00/lvol2 /dev/dsk/c?t?d?
# lvextend -m 1 /dev/vg00/lvol4 /dev/dsk/c?t?d?
# lvextend -m 1 /dev/vg00/lvol5 /dev/dsk/c?t?d?
# lvextend -m 1 /dev/vg00/lvol6 /dev/dsk/c?t?d?
# lvextend -m 1 /dev/vg00/lvol7 /dev/dsk/c?t?d?
# lvextend -m 1 /dev/vg00/lvol8 /dev/dsk/c?t?d?
:
:

You are not required to reboot the system after you have completed all this.

[Kenneth_19]

Oh, forget to answer one of your question:

depends on which stage of the procedure you failed in, you have many ways to recover, if you haven't extend the vg with the new pv, you can just restart the whole process again, and if you failed during the mid of the lvextend, you might need to reduce the mirror that have stale PEs first before you can resume the mirror process starting from the affected volume:

to reduce the mirror of a particular LV

# lvreduce -m 0 /dev/vgxx/lvolx /dev/dsk/c?t?d?

Kenneth

[Ollie R]

Hi,

Another thing you might want to do is to copy the LIF utilities to the mirror disk:

mkboot -b updatediaglif -p ISL -p HPUX -p LABEL -p AUTO /dev/rdsk/c?t?d?

And also, you should set "low quorum" on each of the boot disks so that the system boots if one of the root disks is not available:

mkboot -a "hpux -lq" /dev/dsk/c?t?d?

You can do these actions before or after the "vgextend".

Ollie.

[Zeev Schultz]

...and not forget using lvlnboot after
creating mirror copies.What lvlnboot does
is updating all physical volumes in the volume
group that contains information about boot,root,swap volumes.

# /usr/sbin/lvlnboot -b /dev/vg00/lvol1
# /usr/sbin/lvlnboot -s /dev/vg00/lvol2
# /usr/sbin/lvlnboot -r /dev/vg00/lvol3
# lvlnboot -v

The output of this command is shown in a display like the following:
Boot Definitions for Volume Group /dev/vg00:
Physical Volumes belonging in Root Volume Group:
/dev/dsk/c4t5d0 (10/0.5.0) -- Boot Disk
/dev/dsk/c4t6d0 (10/0.6.0) -- Boot Disk
Boot: lvol1 on: /dev/dsk/c4t5d0
/dev/dsk/c4t6d0
Root: lvol3 on: /dev/dsk/c4t5d0
/dev/dsk/c4t6d0
Swap: lvol2 on: /dev/dsk/c4t5d0
/dev/dsk/c4t6d0
Dump: lvol2 on: /dev/dsk/c4t6d0, 0

[twang]

After mirroring the all LVs on vg00, you may need to perform:
a) pls check for if:
lvol1 on /stand (this is boot lv)
lvol3 on / (this is root lv)
lvol2 is swap lv

b) lvlnboot -r /dev/vg00/lvol3 (root on /)
c) lvlnboot -s /dev/vg00/lvol2 (swap)
lvlnboot -d /dev/vg00/lvol2 (dump) (optional)
d) lvlnboot -R /dev/vg00
e) lvlnboot -v (to confirm all correct)
f) vgcfgbackup /dev/vg00

[Michael Tully]

Be careful when using 'mkboot' that you choose 'rdsk' not 'dsk'. Here is the procedure I use.

# pvcreate -fB /dev/rdsk/cxtydz
# vgcreate /dev/vg00 /dev/dsk/cxtydz
# mkboot /dev/rdsk/cxtydz
# mkboot -a "hpux -lq(;0)/stand/vmunix" /dev/rdsk/cxtydz
# lvlnboot -R
# for LVOL in /dev/vg00/lv*
> do
> echo $LVOL
> lvextend -m 1 $LVOL
> done

# lvlnboot -b /dev/vg00/lvol1
# lvlnboot -s /dev/vg00/lvol2
# lvlnboot -r /dev/vg00/lvol3
# lvlnboot -d /dev/vg00/lvol2
# lvlnboot -R

[Massimo Bianchi]

Hi,
to add a little contribution,

instead of

# mkboot -a "hpux (;0)/stand/vmunix" /dev/dsk/c?t?d?


use

# mkboot -a "hpux -lq(;0)/stand/vmunix" /dev/dsk/c?t?d?

for each of the disks in the vg00.

The "-lq" stands for "disable quorum", to be able to boot even if one of the two disks is in a bad state (NO_HW).


For the replacement procedure, you should:
- put the new disk
- issue a vgcfgrestore towards the new disk, to restore the lvm information on it
vgcfgrestore vg00 /dev/dsk/c?t?d?

- resync the mirrors with "vgsync vg00"


HTH,
Massimo

[Tim D Fulford]

All of the above, good stuff. My spin is why on earth is the utility called MirrorDisk/UX?It clearly does not mirror the disks, it mirrors at a logical volume level. Surely it should be called MirrorLV/UX

Just my 0.02???

Tim

[Learn_1]

Thanks everybody for taking time to reply my question.It really helped a lot to solve the problem.

[Ollie R]

Hi Anwar,

Maybe you could express your appreciation by awarding a few points???

Ollie.

[Ollie R]

Thanks!!!


8O)

[Learn_1]

Hi Everyone,
With reference to ur replies,i am writing down the script for mirroring procedure.if there is any mistake then please do let me know so that i may correct this mistake before applying it to live system.
also i do need some explainination which i will mention in this email.

#pvcreate -Bf /dev/rdsk/c?t?d?
(i will mention this address after checking it with ioscan command))

#vgcreate /dev/vg00 dev/rdsk/c?t?d?
(here should we use rdsk or dsk in all the following locations)

#mkboot dev/rdsk/c?t?d?

#mkboot -a "hp-ux -lq(;0)/stand/vmunix" /dev/rdsk/c?t?d?
(here will you please explain the function of 0 and also if we specify -lq then should we specify the alternate boot path or not?)

#vgextend vg00 /dev/rdsk/c?t?d
#lvextend -m 1 /dev/vg00/lvol1 /dev/rdsk/c?t?d?
#lvextend -m 1 /dev/vg00/lvol2 /dev/rdsk/c?t?d?
#lvextend -m 1 /dev/vg00/lvol3 /dev/rdsk/c?t?d?
(Here does lvol1,lvol2,lvol3 refer to roor,boot,swap volumes.if i am wrong then please explain and correct)

# /usr/sbin/lvlnboot -b /dev/vg00/lvol1
# /usr/sbin/lvlnboot -s /dev/vg00/lvol2
# /usr/sbin/lvlnboot -r /dev/vg00/lvol3
# lvlnboot -v
(here -b=for boot volume,-r=for root,-s=for swap volume,-v=for print verbose messages)

#vgcfgbackup /dev/vg00

so this is the the procedure that i have derived from all your above stated replies.so please do read it and reply if there is any mistake so that i may correct it beore running it to live syste.
Thanks again for replying.

[Massimo Bianchi]

#pvcreate -Bf /dev/rdsk/c?t?d?
(i will mention this address after checking it with ioscan command))

Perfect!



#vgcreate /dev/vg00 dev/rdsk/c?t?d?
(here should we use rdsk or dsk in all the following locations)

with the vgcreate you must use the block special device: /dev/dsk/c.t.d.


#mkboot dev/rdsk/c?t?d?

perferct !

#mkboot -a "hp-ux -lq(;0)/stand/vmunix" /dev/rdsk/c?t?d?
(here will you please explain the function of 0 and also if we specify -lq then should we specify the alternate boot path or not?)

NOT hp-ux BUT hpux !!!


;0 -> don't know, always they told me to use it. i think it is related to hard partitioning, and that is to start at the first partition

-lq -> boot even if other disk is not present. this will automatically be set as alternate link. if in doubt, you can check/set with the command
setboot -> (to check)
setboot -a alternate_HW_path -p primary_HW_path


mkboot -a "hpux -lq(;0)/stand/vmunix" /dev/rdsk/c?t?d?

for both of the disks.

to check

lifcp /dev/rdsk/c?t?d?:AUTO -
strings must be equal

from here always block special device
#vgextend vg00 /dev/dsk/c?t?d
#lvextend -m 1 /dev/vg00/lvol1 /dev/dsk/c?t?d?
#lvextend -m 1 /dev/vg00/lvol2 /dev/dsk/c?t?d?
#lvextend -m 1 /dev/vg00/lvol3 /dev/dsk/c?t?d?
(Here does lvol1,lvol2,lvol3 refer to roor,boot,swap volumes.if i am wrong then please explain and correct)

# /usr/sbin/lvlnboot -b /dev/vg00/lvol1
# /usr/sbin/lvlnboot -s /dev/vg00/lvol2
# /usr/sbin/lvlnboot -r /dev/vg00/lvol3
# lvlnboot -v
(here -b=for boot volume,-r=for root,-s=for swap volume,-v=for print verbose messages)

Perfect, you are just lacking of the dump destination. if not specified, it is the lvol2 usuallt, the swap, because you can loos the data in the swap between a reboot.

#vgcfgbackup /dev/vg00


HTH,
Massimo

[Learn_1]

HI,
I have mirrored the disk according to the procedure specified above.this works fine.the only problem is mentioned below.
"when i remove one of the mirror system disk from which the system is booted up,the system switches to the buddy mirror disk automatically.but when i go to have swap or ioscan info,the system just keeps retreiving these infos.i have waited for 1/2 hours but no result.although the ioscan does show the info but this one is not updated and does show the disk that has already been removed.idf i reboot the server then the system boots from the alternate mirror disk and loads O.E accordingly.after logging in system show swap and ioscan info updated."
so i want to confirm whether i need any command to run when the the system mirror disk from which system is boooted up fails or we just remove it to for testing and buddy mirror disk takes over.one thing to mention that we have to swaps partiotions on system disk and both are mirrored.